Screen



Patented Sept. 17, 1935 UNITED STATES NT OFFICE Application June 20, 1934, Serial No. 731,455

4 Claims.

Our invention relates to a device for screening wet material, such as distillery slop, and has reference more particularly to a screen in which the material to be filtered is moved and distributed on the screen against the tendency of the material to be filtered to move gravitationally on the screen.

Another object of the invention is to provide a screen with means to insure efficient distribution of the material to be filtered all over the screen.

In the appended drawing forming part of this application, Figure 1 is a plane of a device embodying our invention, and

Figure 2 is a vertical section on line 2-2, Figure 1.

Referring to the drawing, 3 is a box disposed at an angle to the horizontal, to get the desired amount of inclination for the perforated screen 4 provided within the box 3. The box has at the lower end an extension 5 with horizontal sides to form a sluce whereinto the material to be filtered is charged by any suitable means, not shown.

To distribute the material to be filtered from the sluce of the box over the screen 4, we employ a series of paddles 6 mounted on chains 1 engaged by sprockets 8, the shafts for which are located in the sides of the box. Means for mov ing the sprockets, chains and paddles are not shown. The paddles are normally maintained in contact with the screen by gravity, and'from the direction of rotation of the sprockets'shown in the drawing, it will be seen that the paddles move up the inclined screen or against the tendency of the material to be screened to mov downward on the inclined screen.

The spaces between adjacent paddles and the screen in contact with the paddles, form a compartment or scoop which takes the material located in 5 of the box 3 and moves it along the screen, during its travel naturally losing the liquid consistency thereof soon after leaving the level of liquid in the box, but still continuing to carry and distribute the semi-drled portion thereof over the screen, so that filtration takes place not directly through the screen but through a layer of material on the screen.

To prevent the spilling of the'liquid portion of the material included between adjacent paddles that are in engagement with the screen, due

to the slope of the screen as it emerges, we provide' a baffle 9, a portion of which is within. the liquid part and a portion'above the liquid, the paddles passing under said battle as they travel from the liquid to the dry part of the screen. The bafile also prevents spilling of liquid that may be caused by eddies or vibration due to the motion of the paddles by the chains onthe screen. The baffle 9, as shown, is hinged at its lower end 5 so that its contact with the passing paddles is maintained by gravity, tending to swing the baflle on its pivot.

Under the action of gravity, material distributed on the screen by the baflle has a tendency 10 to slip or move along the screen and through it, under the action of gravity, while the baffles try to move the material against that tendency, the baffles maintaining a substantial uniform thickness of the material on the screen. The ma- 1 terial filtered through the screen. finds its outlet through a passage It] provided in the box below the screen at its lowest part.

The baflie 9 prevents removal of thickened material or semi-solids from between the paddles 20 while said paddles are travelling beneath the surface of the liquid. It has been found in actual practice that if this bafile is not present, the passage of the paddles through the liquid causes a disturbance which actually empties out 25 the'settled material from therebetween and prevents a proper functioning of the screen.

We claim:

1. In a screen, an inclined box having at its lower part means for receiving material to be 30 screened, a similarly inclined screen located in the box having a portion thereof immersed in the material to be screened, a series of travelling paddles adapted to move in the box over the screen, to distribute the material to be filtered 35 against the gravitational tendency of the material to move on the screen, and a baflie located withinthe box inclined similarly to the screen and engaging the paddles as they move over the screen while passing from the immersed part of 40 the screen.

2. In a screen, an inclined box having at its lower part means for receiving material to be screened, a similarly inclined screen in the box having a portion thereof immersed in the mate- 45 rial to be screened, a series of travelling paddles adapted to move in the box over the screen to distribute the material to be filtered against the gravitational tendency of the material to move on the screen, and a bathe in the box inclined 50 similarly to the screen engaging gravitationally the paddles as they move over the screen in passing from the immersed part of the screen.

3. In a screen, an inclined box having at its lower part means for receiving material to be 55 screened, a screen located in the box having a portion thereof immersed in the material to be screened, a series of travelling paddles adapted to move in the box over the screen to distribute the material to be filtered against the gravitational tendency of the material to move on the screen, and a battle pivotally mounted within the box and engaging the paddles as they move over the screen while passing from the immersed part of the screen.

4. In a, screen, an inclined box having at its lower part means for receiving material to be screened, a similarly inclined screen located in the box having a portion thereof immersed in the material to be screened, a series of travelling paddles adapted to move in the box over the screen to distribute the material to be filtered against the gravitational tendency of the material to move on the screen, and a battle located within the box inclined similarly to the screen and having a portion thereof immersed in the material to be screened and engaging the paddies gravitationaly as they move over the screen while passing from the immersed part of the 10 screen.

JAMES RUSSELL COFFEY. HARRY ADAMS. 

